Question

A box has 8 beads of the same size, but all are different colors. Tamy draws a bead randomly from the box, notes its color, and then puts the bead back in the box. She repeats this 3 times. What is the probability that Tamy would pick a red bead on the first draw, then a white bead, and finally a red bead again?

Answer 1

Since there is only one bead of each color, and they are being placed back into the box after each draw, at any given moment BEFORE a draw there's 8 beads. So the probability for each bead/color is 1/8.

Answer 2

If they weren't being placed back in, it'd be 1/8 for the red bead, then 1/7 for the white head, then 0/6 for the red bead again.